There is a substantial body of literature directed to the use of various acid catalysts to effect intramolecular and intermolecular condensation of amino compounds. U.S. Pat. No. 2,073,671 and U.S. Pat. No. 2,467,205 constitute early prior work on the use of acid condensation catalysts to condense amino compounds. U.S. Pat. No. 2,073,671 discusses, in a general fashion, the catalytic intermolecular condensation of alcohols and amines or ammonia using the same phosphate catalysts later favored by U.S. Pat. No. 2,467,205 for the intramolecular condensation of amines. The two patents are not in harmony over the use of other materials as catalysts. To illustrate this point, U.S. Pat. No. 2,073,671 states:
"Alumina, thoria, blue oxide of tungsten, titania, chromic oxide, blue oxide of molybdenum and zirconia have been mentioned in the literature for use as catalysts in carrying out these reactions but their effectiveness is so low that no practical application has been made of their use." PA0 "silica gel, titania gel, alumina, thoria, boron phosphate, aluminum phosphate, and the like." PA0 ". . . a heated catalyst or contact mass containing phosphorus and especially one or more of the oxygen acids of phosphorus, their anhydrides, their polymers, and their salts; for example, orthophosphoric acid, metaphosphoric acid, pyrophosphoric acid, phosphorous pentoxide, dimetaphosphoric acid, trimetaphosphoric acid, primary ammonium phosphate, secondary ammonium phosphate, normal ammonium phosphate, ammonium metaphosphate, secondary ammonium pyrophosphate, normal ammonium pyrophosphate, aluminum phosphate, aluminum acid phosphate and mixtures of two or more of such materials."
whereas U.S. Pat. No. 2,467,205 in describing the self-condensation of ethylenediamine (EDA) under vapor phase conditions, to initially produce ethyleneamines, but after recycle, eventually generates piperazine (PIP) through multistep condensation reactions, followed by deamination, recommends "dehydration catalysts" which are thereafter characterized as
U.S. Pat. No 2,073,671 describes the condensation catalyst in the following terms:
whereas U.S. Pat. No. 2,467,205 describes one of the preferred catalysts as "basic aluminum phosphate".
U.S Pat. No. 2,454,404 describes the "catalytic deamination of alkylene polyamines" by reacting DETA vapor over solid catalysts such as activated alumina, bauxite, certain aluminum silicates such as kaolin and oxides of thorium, titanium and zirconium.
U.S. Pat. Nos. 2,073,671 and 2,467,205 demonstrate a common experience in using aluminum phosphate as a condensation catalyst to produce aliphatic amines, and U.S. Pat. Nos. 2,454,404 and 2,467,205 contemplate the other solid catalysts for deamination of amines to make heterocyclic noncyclic amines. In general, the reaction conditions under which deamination to effect cyclization occurs are more severe than those employed for condensation to generate noncyclic molecules, all other factors being comparable.
U.S. Pat. Nos. 4,540,822, 4,584,406 and 4,588,842 depict the use of Group IVB metal oxides as supports for phosphorus catalysts used to effect the condensation of amino compounds with alkanolamines.
U.S. Pat. No. 4,683,335 describes the use of tungstophosphoric acid, molybdophosphoric acid or mixtures deposited on titania as catalysts for the condensation of amines and alkanolamines to make polyalkylenepolyamines.
U.S. Pat. Nos. 4,314,083, 4,316,840, 4,362,886 and 4,394,524 disclose the use of certain metal sulfates as useful catalysts for the condensation of alkanolamine and an amino compound. No distinction is made between the sulfur compounds in respect to catalytic efficacy. Sulfuric acid is as good as any metal sulfate, and all metal sulfates are treated as equivalents. At column 8 of U.S. Pat. No. 4,314,083, it is noted that boron sulfate "gave extremely high selectivity at a low level" of EDA. However, selectivity in general was shown to increase with an increase of EDA relative to monoethanolamine (MEA) in the feed. The only specific metal sulfates disclosed in the patents are antimony sulfate, beryllium sulfate, iron sulfate and aluminum sulfate.
In the typical case of the manufacture of alkyleneamines, mixtures with other alkyleneamines (including a variety of polyalkylenepolyamines and cyclic alkylenepolyamines) are formed. The same holds true when the object of the process is to produce polyalkylenepolyamines whether acyclic or cyclic, in that a variety of amino compounds are also formed. Each of these cyclic and acyclic alkyleneamines can be isolated from the mixture.
The acid catalyzed condensation reaction involving the reaction of an alkanolamine with an amino compound in the presence of an acidic catalyst is believed to proceed through the mechanism of esterifying free surface hydroxyl groups on the acid catalyst with the alkanolamine and/or by protonating the alkanolamine in the presence of the acid catalyst, followed by loss of water and amine condensation of the ester or the hydrated species, as the case may be, to form the alkyleneamine. Illustrative prior art directed primarily to the cyclic polyalkylenepolyamines (heterocyclic polyamines), but not necessarily limited to the aforementioned acid condensation reaction, are: U.S. Pat. Nos. 2,937,176, 2,977,363, 2,977,364, 2,985,658, 3,056,788, 3,231,573, 3,167,555, 3,242,183, 3,297,701, 3,172,891, 3,369,019, 3,342,820, 3,956,329, 4,017,494, 4,092,316, 4,182,864, 4,405,784 and 4,514,567; European Pat. Applications 0 069 322, 0 111 928 and 0 158 319; East German Pat. No. 206,896; Japanese Pat. Publication No. 51-141895; and French Pat. No. 1,381,243. The evolution of the art to the use of the acid catalyzed condensation reaction to generate acyclic alkyleneamines, particularly acyclic polyalkylenepolyamines, as the predominant products stemmed from the initial disclosure in U.S. Pat. No. 4,036,881, though earlier patent literature fairly well characterized such an effect without labeling it so, see U.S. Pat. No. 2,467,205, supra. The acid catalysts are phosphorus compounds and the reaction is carried out in the liquid phase. The trend in this catalyst direction was early set as demonstrated by U.S. Pat. Nos. 2,073,671 and 2,467,205, supra. A modification of this route includes the addition of ammonia to the reaction, see, for example, U.S. Pat. No. 4,394,524 and U.S. Pat. No. 4,463,193 for the purpose of converting alkanolamine such as MEA in situ to alkylene amine such as EDA by reaction with ammonia, and the EDA is in situ reacted with MEA according to the process of U.S. Pat. No. 4,036,881 to form alkyleneamines.
A summary of the prior art employing acid catalysts for making alkyleneamines is set forth in Table I below.
TABLE I ______________________________________ CITATION CATALYST TYPE REACTANTS ______________________________________ U.S. 2,467,205 Silica gel, titania gel, Vapor phase con- alumina, thoria, aluminum sation of EDA over phosphate. Preferred a fixed bed of the catalyst is basic catalyst, multipass aluminum phosphate process shifts from polyethylene-poly- amines with the first few cycles. U.S. 4,036,881 Phosphorus containing sub- Alkanolamine and tances selected from the alkyleneamine in group consisting of acidic liquid phase metal phosphates, phos- reaction. phoric acid compounds and their anhydrides, phos- phorus acid compounds and their anhydrides, alkyl or aryl phosphate esters, alkyl or aryl phosphite esters, alkyl or aryl substi- tuted phosphorous and phosphoric acids wherein said alkyl groups have from 1 to about 8 carbon atoms and said aryl groups have from 6 to about 20 carbon atoms, alkali metal monosalts of phosphoric acid, the thioanalogs of the foregoing, and mix- tures of the above. U.S. 4,044,053 Phosphorus containing sub- Alkanepolyols and stances selected from the alkyleneamine in group consiting of acidic liquid phase metal phosphates, phos- reaction. phoric acid compounds and their anhydrides, phos- phorus acid compounds and their anhydrides, alkyl or aryl phosphate esters, alkyl or aryl phos- phite esters, alkyl or aryl substituted phosphorous acids and phosphoric acids wherein said alkyl groups have from 1 to about 8 carbon atoms and said aryl groups have from 6 to about 20 carbon atoms, alkali metal monosalts of phosphoric acid and mix- tures of the above. U.S. 4,314,083 Salt of a nitrogen or sul- Alkanolamine and fur containing substance an alkyleneamine in or the corresponding acid. liquid phase reaction. U.S. 4,316,840 Metal nitrates and sulfates Reforming linear including zirconium polyamines. sulfate. U.S. 4,316,841 Phosphate, preferably Reforming linear boron phosphate. polyamines. U.S. 4,324,917 Phosphorus-containing Alkanolamine and cation exchange results. an alkyleneamine in liquid phase reaction. U.S. 4,362,886 Arsenic, antimony or Alkanolamine and bismuth containing com- an alkyleneamine in pounds. Antimony sulfate liquid phase specifically disclosed. reaction. U.S. 4,399,308 Lewis acid halide. Alkanolamine and an alkyleneamine in liquid phase reaction. U.S. 4,394,524 Phosphorus-containing Ammonia, alkanol- substance or salt of a amine and an alkyl- sulfur-containing sub- amine in liquid stance, or the corres- phase reaction. ponding acid. U.S. 4,448,997 Reacts alumina with EDA with MEA. phosphoric acid, adds ammonium hydroxide. U.S. 4,463,193 Group IIIB metal acid Ammonia, alkanol- phosphate. amine and an alkyleneamine. U.S. 4,503,253 Supported phosphoric acid. Ammonia, alkanol- amine and an alkyleneamine. U.S. 4,521,600 Select hydrogen phos- Alkanolamine and phates and pyrophosphates. an alkyleneamine. U.S. 4,524,143 Phosphorus impregnated Alkanolamine and onto zirconium silicate an alkyleneamine. support. U.S. 4,540,822 Phosphorus compound Alkanolamine and deposited on a Group IVB an alkyleneamine, metal oxide support. regenerates the catalyst with O.sub.2 -containing gas. U.S. 4,547,591 Silica-alumina alone or in An ethyleneamine combination with an acidic and an alkanol- phosphorus cocatalyst. amine; ethylene- amines; or ammonia and an alkanol- amine. U.S. 4,550,209 An intercalatively cata- EDA and MEA. lytically active tetravalent zirconium polymeric reac- tion product of an organo phosphonic acid or an ester thereof with a com- pound of tetravalent zir- conium reactive therewith. U.S. 4,552,961 Phosphorus amide Alkyleneamine and compound. alkanolamine and/or alkylene glycol. U.S. 4,555,582 Phosphorus chemically MEA and EDA. bonded to a zirconium silicate support. U.S. 4,560,798 Rare earth metal or MEA. strontium acid phosphate. U.S. 4,578,517 Group IIIB metal acid Ammonia or p-/s- phosphate. amine and alkanolamine. U.S. 4,578,518 Thermally activated, cal- MEA and EDA. cined, pelleted titania con- taining titanium triphos- phate. " . . . the titania that was used was . . . anatase." (Col. 9, lines 18-19). U.S. 4,578,519 Thermally activated, cal- MEA and EDA cined, pelleted titania with with optional chemically bonded phos- recycle of DETA. phorus derived from polyphosphoric acid. U.S. 4,584,405 Activated carbon, option- MEA and EDA. ally treated to incorporate phosphorus. Activated car- bon may be washed with strong mineral acid to re- move impurities followed by water wash. Optional treatment follows. U.S. 4,584,406 Pelleted Group IVB metal MEA and EDA. oxide with chemically bonded phosphorus de- rived from phosphoryl chloride or bromide. U.S. 4,588,842 Thermally activated pel- MEA and EDA. leted Group IVB metal oxide with chemically bonded phosphorus. U.S. 4,605,770 Group IIA or IIIB metal Alkanolamine and acid phosphate. and alkyleneamine "in liquid phase". U.S. 4,609,761 Thermally activated MEA and EDA. pelleted titania with chemi- cally bonded phosphorus. U.S. 4,612,397 Thermally activated MEA and EDA. pelleted titania with chemi- cally bonded phosphorus. U.S. 4,617,418 Acid catalysts, mentions Ammonia, alkanol- "beryllium sulfate". amine and an alkyleneamine "under vapor phase conditions". Japanese Patent Variety of phosphorus and Ammonia, alkanol- Application metal phosphates including amine and ethyl- #1983-185,871, Group IVB phosphates. eneamine, with Publication ammonia/alkanol- #1985-78,945 amine molar ratio greater than 11. U.S. 4,683,335 Tungstophosphoric acid, Claims reaction of molybdophosphoric acid or MEA and EDA, mixtures deposited on but discloses self- titania. Examples 2-7 condensation characterize titania surface reaction of EDA areas of 51, 60 and 120 and DETA. m.sup.2 /gm. Japanese Patent Group IVB metal oxide Ammonia and Application with bonded phosphorus. MEA. #1985-078,391, Publication #1986-236,752 Japanese Patent Group IVB metal oxide Ammonia and Application with bonded phosphorus. MEA. #1985-078,392, Publication #1986-236,753 U.S. 4,698,427 Titania having phosphorus Diethanolamine thermally chemically and/or hydroxy- bonded to the surface ethyldiethylene- thereof in the form of triamine in EDA. phosphate bonds. U.S. 4,806,517 Pelleted Group IVB metal MEA and EDA. oxide with phosphorus thermally chemically bonded to the surface thereof. European Titania and zirconia MEA and EDA. Patent chemically bonded to Application phosphorus. 331,396 ______________________________________
A summary of additional prior art for making alkyleneamines is set forth in Table II below.
TABLE II ______________________________________ CITATION CATALYST TYPE REACTANTS ______________________________________ Japanese Patent Niobium-containing Ammonia, alkyl- Application substance. eneamine and #1987-312,182, alkylene glycol. Publication #1989-153,659 Japanese Patent Niobium-containing Ammonia, alkylene- Application substance added to amine and #1987-325,274, water-containing liquid alkanolamine. Publication #1989-168-647 Japanese Patent Niobium oxide obtained Ammonia, alkylene- Application from niobium alkoxide. amine and #1987-321,348, alkanolamine. Publication #1989-163,159 Japanese Patent Niobium pentoxide. Ammonia, alkylene- Application amine and #1989-314,132, dialkanolamine. Publication #1989-157,936 Japanese Patent Niobium-containing Ammonia, alkylene- Application substance. amine and #1987-290,652, alkanolamine. Publication #1989-132,550 Japanese Patent Tantalum-containing Ammonia, alklyene- Application substance. amine and #1987-142,384, alkanolamine. Publication #1989-307,846 European Patent Mixed oxide containing Ammonia, alkylene- Application niobium oxide. amine and 315,189 alkanolamine. European Patent Niobium-containing Ammonia, alkylene- Application subsance supported amine and 328,101 on a carrier. alkanolamine. Japanese Patent Titania and zirconia MEA and EDA. Application chemically bonded with #1989-048,699, phosphorus in the form Publication of a hydroxy-containing #1990-006,854 phosphate group. Japanese Patent Niobium oxide and Ammonia, alkylene- Application titania, alumina, silica amine and #1988-262,861, or zirconia. alkanolamine. Publication #1990-002,876 Japanese Patent Niobium oxide Ammonia, alkylene- Application with an acid. amine and #1988-290,106, alkanolamine. Publication #1990-000,735 Japanese Patent Niobium-containing Ammonia, alkylene- Application substance on a carrier. amine and #1988-027,489, alkanolamine. Publication #1990-000,736 Japanese Patent Three constituent cata- Alcohol or aldehyde Application lyst-copper; one or more and ammonia, a #1988-261,366 elements selected from primary amine or a Publication chromium, manganese, secondary amine. #1990-000,232 iron and zinc; and a platinum group element. Japanese Patent Four constituent cata- Alcohol or aldehyde Application lyst-copper; one or more and ammonia, a #1988-261,368, elements selected from primary amine or a Publication chromium, manganese, secondary amine. #1990-000,233 iron, cobalt, nickel and zinc; a platinum group element; and one or more elements selected from lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium and barium. Japanese Patent Four constituent cata- Alcohol or aldehyde Application lyst-copper; one or more and ammonia, a #1988-261,369, elements selected from primary amine or a Publication chromium, manganese, secondary amine. #1990-000,234 iron, cobalt, nickel and zinc; a platium group element; and one or more elements selected from aluminum, tungsten and molybdenum. ______________________________________
The market demand for AEEA has been progressively increasing in recent years. It would be desirable to satisfy the existing demand from a cost standpoint by modifying slightly the commercial processes directed to the manufacture of higher polyalkylene polyamines such as triethylenetetramine (TETA), tetraethylenepentamine (TEPA) and pentaethylenehexamine (PEHA) from suitable starting raw materials to the production of AEEA as a major product.
It would be desirable to have continuously produced compositions, generated by the reaction of MEA and EDA or other suitable starting raw materials over a fixed bed of a condensation catalyst under commercial conditions, that are rich in AEEA and that are not disproportionately high in PIP and other cyclics.
The above features are provided by this invention.